29 A PRACTICAL AND SHORT STEP TOTAL SYNTHESES OF ERGOT ALKALOIDS
-
- Somei Masanori
- Faculty of Pharmaceutical Sciences, Kanazawa University
-
- Makita Yoshihiko
- Faculty of Pharmaceutical Sciences, Kanazawa University
-
- Yamada Fumio
- Faculty of Pharmaceutical Sciences, Kanazawa University
Bibliographic Information
- Other Title
-
- 29 短工程かつ実用的な麦角アルカロイド全合成
Abstract
We have now established a common and practical short step synthetic method, as shown in chart 5, which is widely applicable for various ergot alkaloids and their analogs only by changing a reagent in each step and without changing the reaction type. Thus, when 2-methyl-3-buten-2-ol is used as an olefin in the second step, X, L, R^1, and R^2 of the formulas in chart 5 are I, OH, H, and H, respectively, and (±)-6,7-secoagroclavine (9) was synthesized in 36% overall yield. In the case of using 2-methoxy-2-methyl-3-buten-1-ol as an olefin, X, L, R^1, and R^2 are I, OMe, OH, and H, respectively, and (±)-6-norchanoclavine-I (20 or G) and (±)-6-norisochanoclavine-I (23 or G, R^1=H, R^2=OH) were obtained in good overall yields. These synthetic alkaloids were readily converted to (±)-chanoclavine-I (22 or I) or (±)-isochanoclavine-I (25 or I, R^1=H, R^2=OH), respectively. Treatment of 25 with thionyl chloride produced (±)-agroclavine (26). Since the alkaloid (26) has already been led to festuclavine, costaclavine, setoclavine, and isosetoclavine, formal syntheses of these alkaloids were also achieved. For the syntheses of above mentioned ergot alkaloids in large quantity, experimental procedures were extensively examined and now we can carry out successfully each of all steps involved in chart 1 in 50g scale.
Journal
-
- Symposium on the Chemistry of Natural Products, symposium papers
-
Symposium on the Chemistry of Natural Products, symposium papers 27 (0), 214-221, 1985
Symposium on the Chemistry of Natural Products Steering Committee
- Tweet
Details 詳細情報について
-
- CRID
- 1390282681050615296
-
- NII Article ID
- 110006678461
-
- ISSN
- 24331856
-
- Text Lang
- ja
-
- Data Source
-
- JaLC
- CiNii Articles
-
- Abstract License Flag
- Disallowed